DESCRIPTION: A marked increase in the prevalence of sleep apnea, insomnia and hypersomnia in women has been noted during mid-life aging. Despite these observations and the biologic rationale that menopausal changes are likely to profoundly affect sleep, research on the pathogenesis of sleep disorders in women as they pass through menopause is lacking. The long-range goals of this longitudinal study of mid-life aging in women are to understand the role of menopause in the occurrence and progression of sleep apnea, insomnia and hypersomnolence and ultimately to formulate clinical strategies for intervention and prevention of the increased risk of theses dyssomnias in mid-life. Understanding the role of menopause in dyssomnia occurrence is particularly important because millions of women are exposed to menopausal changes yearly and because the hypothesized outcomes, particularly sleep apnea, are associated with cardiovascular and behavioral morbidity and mortality. The results of this study will have direct application o medical care for women in mid-life. The proposed study is designed to (1) definitively test the hypothesis that sleep apnea, insomnia and hypersomnia incidence and progression increase in peri and post menopause, relative to premenopause; (2) test the hypothesis that the association of sleep disorders and mid-life aging is attributable to menopause-related changes in body habitus; (3) test the hypothesis that peri and post menopausal women with hormonal replacement therapy, relative to those without, have lower incidence of dyssomnias; (4) determine the effect of type of menopause on dyssomnia occurrence in mid-life, and (5) establish a cohort of 150 women with data on menopausal status to be merged with ongoing data collected by the parent study on functional status, health care costs, cardiovascular and behavioral outcomes for future analyses. A robust prospective longitudinal study design with adequate power to address the above specific aims will be used. Semiannual home polysomnography studies and other measurement of dyssomnia during peri and post menopause will be conducted on a cohort of 150 women on whom up to 8 years of polysomnography data during premenopause have already been collected as part of the parent study, the Wisconsin Sleep Cohort Study. The specific aims, will be addressed using standard definition of menopause and dyssomnias, with longitudinal multivariate models able to control for confounding factors and to investigate interactions.